Multi-domain indoor environmental quality in intensive care units from a healthcare worker perspective: An...

The well-being of healthcare workers in ICUs is an important interdisciplinary issue, bridging occupational health, clinical medicine, and environmental design. While interventions have focused on staffing and workload management, the ICU environment's impact on staff remains underexplored. Most previous studies have addressed indoor environmental quality (IEQ) from the patient perspective, lacking comprehensive multi-domain assessments in relation to staff experience. This study applied methods from building environmental engineering and occupational health to objectively and subjectively evaluate IEQ in a university hospital ICU in Japan, examining associations between IEQ and work productivity.

From July to September 2023, environmental parameters-temperature, humidity, air quality, illuminance, and noise-were measured. Healthcare workers also evaluated their satisfaction with thermal, air, lighting, and acoustic environments, and work productivity (concentration, communication). Multiple linear regression analyses were conducted to examine the associations between satisfaction with IEQ domains and (1) overall environmental satisfaction, and (2) work productivity.

(1) Although the average temperature across 12 ICU beds was 23.2 °C, single-bed rooms were approximately 2 °C cooler, contributing to thermal dissatisfaction. (2) Dissatisfaction with air quality was relatively low, consistent with favourable CO₂ and PM_2.5 levels. (3) Dissatisfaction with lighting stemmed mainly from insufficient daylight; bedsides with daylight had an average illuminance of 754 lx versus 218 lx without. (4) Acoustic dissatisfaction was highest; the average A-weighted equivalent continuous sound levels were 57.7  dB(A) over 24 h and 54.5  dB(A) during nighttime, exceeding the guideline value of 45  dB(A) even at night. (5) Satisfaction with lighting and acoustic environments was significantly associated with overall environmental satisfaction; lighting satisfaction was also positively linked to concentration.

Optimising multi-domain IEQ, particularly lighting and acoustic conditions, may enhance ICU staff productivity and well-being.

These findings support cross-disciplinary collaboration in hospital design and management, promoting holistic environmental strategies for healthcare workforce support.